Pilonidal disease is a common surgical problem that was first described in 1833. The name derives from the Latin pilus (hair) and nidus (nest) (Miller et al, 2003).
Its incidence is estimated to be 26 cases per 100 000, with those affected being primarily men aged 20–30 years (Søndenaa et al, 1995; Al-Khamis et al, 2010). It is an acquired disease that originates in the hair follicles of the sacrococcygeal area (Farrell and Murphy, 2011). The disease is associated with local trauma, obesity, smoking, sedentary occupation and a hirsute body (Notaro, 2003). Obstruction of the hair follicles may cause abscess formation in the subcutaneous tissues, while entrapment of hair may cause a foreign body reaction, also leading to the formation of an acute abscess. These can both lead to complex disease characterised by chronic or recurrent infection with extensive, branching sinus tracts (Bendewald and Cima, 2007).
Pilonidal disease causes a significant decrease in the quality of life and has negative physical and psychological effects. The need for wound treatments over long periods of time and the inability to reconcile work with illness affect patients and bring significant economic costs to the healthcare system.
The majority of patients present with a painful, acute abscess on the natal cleft, which often resolves with the formation of sinus tracts toward the skin. Prolonged neglect of symptoms and successive abscess formation may lead to complex disease. Malignant transformation occurs in about 0.1% of patients and usually involves squamous cell carcinoma (de Bree et al, 2001; White et al, 2012; Pandey et al, 2014). Patients are at risk of malignancy if the disease is neglected for a long period of time (Michalopoulos et al, 2017).
Various surgical techniques are used in its treatment and there is a lack of consensus concerning the optimal approach to complex pilonidal disease (Al-Khamis et al, 2010). Treatments vary from simple excision of the pilonidal sinus followed by primary closure of the defect, to wound healing by secondary intention (Gencosmanoglu and Inceoglu, 2005), excision with a Limberg transposition flap (Eryilmaz et al, 2003; Cihan et al, 2006), fasciocutaneous V-Y advancement flap (Schoeller et al, 1997), excision with Z-plasty (Lamke et al, 2009; Banasiewicz, 2013), elliptical rotation flap (Neşşar et al, 2004), and other rotation advancement fasciocutaneous flaps (Schoeller et al, 1997).
In addition to the variation in treatment, there is a lack of a consensus regarding wound care. The location of the wound is challenging. Very exudative wounds in places where wound care is difficult, sometimes close to the anus, are associated with recurrent infections, which also increases the economic burden (Bendewald, 2007; Dumville, 2015).
Patients managed using open healing have particularly challenging wounds. However, surgeons may choose this approach, despite longer healing times, since it is associated with a decreased risk of recurrence (Søndenaa et al, 1995). The literature reports that the risk of recurrence of a pilonidal sinus after surgical treatment varies but may be in the 40-50% range (Notaro, 2003).
Negative pressure wound therapy applied to open surgical wounds for pilonidal disease has been suggested to reduce healing times and costs and is an emerging option for the care of complex and/or recurrent pilonidal disease (Farrell and Murphy, 2011).
This study describes a case of complex pilonidal disease managed with local excision and negative pressure wound therapy followed by a split-thickness skin graft.
Case presentation
A 40-year-old man was referred by a district hospital for a consultation regarding plastic surgery at the authors' department for multiple fistulas at the sacrococcygeal region. The patient was a smoker, had a BMI of 24, a history of depression, chronic sinusitis, dyslipidemia, previous inguinal herniorrhaphy (hernia repair) and was taking diazepam, trazodone and ethyl loflazepate.
At physical examination, he was seen to have sacrococcygeal pilonidal disease with multiple and complex fistulas bilaterally covering an area of about 15 cm x 10 cm.
It was decided the patient was suitable for elective surgical repair. Routine preoperative laboratory work-up was done and results were considered within normal values.
On the day of surgery, under general anaesthesia, he was placed in the prone position and given ceftriaxone 1 g intravenously 30 minutes before a skin incision was made. After skin preparation, surgical drapes were placed, and the anus covered with sterile gauze. All identified fistula tracts were marked with methylene blue and the area to be excised was marked on the skin with a sterile skin marking pen (Figure 1).
An en-bloc excision of the skin and subcutaneous tissue up to the presacral fascia was performed, guided by the methylene blue markings (Figure 2). The area excised was sent for histological examination (Figure 3). Bilateral local flap advancement was done at the presacral fascia level to reduce surgical wound size. Good haemostasis with electrocautery was achieved. In the places that allowed for skin closure, suturing was performed in layers with Vicryl 2/0 and Monocryl 3/0 (Figure 4).
Figures 6-8. Second surgery and postoperative healing
After wound cleansing with sterile saline, an Acticoat silver-coated antimicrobial barrier dressing 10 cm x 10 cm (Smith and Nephew, UK) was placed over the wound to reduce the risk of infection. Negative pressure wound therapy was then applied with a foam dressing using a negative pressure inpatient care system to achieve better secondary healing results (Figure 5). No specific postoperative patient positioning was recommended, no pressure care mattress was used and the patient was allowed to lie freely on his back.
Histopathologic examination described a flap of skin and subcutaneous tissue measuring 16 cm x 13 cm, with a longitudinal sinus tract of 6 cm with multiple fistulas, some with hair inside. It was considered a pilonidal cyst with partially epidermal coverage, with fibrosis and moderate inflammatory infiltrate present.
The patient was discharged 2 days after surgery with an oral selective COX-2 inhibitor (etoricoxib) and paracetamol 1 g three times per day to control inflammation and pain. The negative pressure system dressing was changed four times during the 24-day period between the first and second surgical procedures. The silver dressing was placed for the first 7 days after surgery.
Before the second procedure, 3 weeks after the first surgery, the wound bed was clean and filled with granulation tissue—ideal conditions for skin graft plasty. At the time, the wound was covered with a conventional dressing. The second intervention was scheduled 4 days later (Figure 6). The negative pressure system was changed four times with a mean interval of 4-5 days.
Under general anaesthesia, and in the same prone position, the patient had the wound cleaned with saline irrigation and gentle and superficial debridement with sterile gauze. A partial-thickness skin graft was collected from the posterior thigh and was placed to cover the wound (Figure 7). Gauze with povidone iodine for the tie-over dressing was placed on top. An intrathecal catheter with ropivacaine was placed for pain control. It was removed before discharge, but only after pain had remained controlled without this drug for 4 hours.
At the fifth postoperative day, the patient was discharged for outpatient wound care consultation. Over the following 3 weeks, he had four dressing changes, with paraffin gauze and antibiotic ointment applied. At the 21st postoperative day, the wound had healed completely with successful skin graft integration (Figure 8). The patient was discharged from outpatient care and returned to normal daily activities.
Discussion
Pilonidal disease is a psychologically and physically debilitating disease that has a negative impact on the quality of life and professional activity, as well as being an economic burden on the healthcare system.
Negative pressure wound therapy has recently been used in the treatment of an open surgical wound after excision of complex pilonidal disease because of the low success of conventional excision and primary closure treatments. The approach without primary closure is important in complex pilonidal disease with large lesion areas; however, for simple non-recurrent pilonidal cysts without complex fistulas, or other signs of complex chronic or advanced disease, evidence comparing surgical closure with open healing is not adequate for conclusions to be drawn (Al-Khamis, 2010).
Local flaps are another alternative. Although results regarding treatment of pilonidal disease with local flaps such as superior or inferior gluteal artery based flaps have been promising (Mu et al, 2005; Darwish and Hassanin, 2010), the authors decided not to perform such a procedure because of the size and bilateral nature of the lesion.
Excision followed by healing by secondary intention with negative pressure wound therapy was performed in this case. The decision to use this surgical technique and method of closure based on patient characteristics is in line with the recommendations of one of the few systematic reviews in this subject by Al-Khamis et al (2010). Although surgically closed sinuses generally heal more quickly, they are more likely to recur, so choosing between the two treatment options should be based on patient and surgeon preferences (Al-Khamis et al, 2010).
Regarding the use of negative pressure wound therapy for the treatment of pilonidal disease, there is still a gap in the literature, with the majority of studies being observational case reports (Lynch et al, 2004; Bendewald et al, 2007). The review by Farrell and Murphy (2011) included 14 patients from five different case reports. There were some difference in treatment between cases but it concluded that negative pressure wound therapy may be an emerging option for pilonidal disease management.
Regarding the time of onset of negative pressure wound therapy, in the cases reviewed by Farrell and Murphy (2011), some patients were started on the treatment intraoperatively while others began it 48 hours after surgery. The duration of each negative pressure therapy dressing was 3 days; however, some patients had no record of dressing changes being performed. Of the 14 patients, only 3 had non-relapsed complex pilonidal disease and most of the remaining patients had recurrent disease with up to eight previous surgeries. In 12 patients, negative pressure wound therapy was used at -125 mmHg and 2 patients were treated with negative pressure wound therapy at -50 mmHg.
The case study described here differed from the above studies in the local pressure used. In this case, the pressure was set to -80 mmHg, a lower value than most of those in the series of cases reported by Farrell and Murphy (2011). However, wound closure time was similar, and the duration of wound healing (6 weeks) from the first surgery to the discharge from the outpatient clinic was inferior to those reported by Farrell and Murphy (2011). However, the authors of the present study chose, in line with the manufacturer's instructions, to use the negative pressure wound therapy system for longer—sometimes for more than 3 days—which probably resulted in lower costs than the studies analysed by Farrell and Murphy (2011).
The authors stress that only four negative pressure wound therapy dressings were used between the first and second intervention. The total costs of wound care after surgical excision of the lesion and before grafting—with four dressings made with the vacuum system, plus two reservoirs, the silver dressing and four consultations for wound care—was about €366. If the patient had been treated with conventional wound care with a daily dressing change (with an estimated increment of about 7 days when not using the negative pressure wound therapy system), the cost would have been about €720.
The authors therefore believe negative pressure wound therapy allowed an earlier discharge with a probable reduction of costs, as well as greater patient mobility and comfort while he was receiving outpatient treatment between interventions.
Regarding antibiotic therapy, the authors chose to perform prophylactic antibiotic treatment only at the time of the surgical interventions, since they do not believe empirical antibiotics have a role in the management of surgically excised pilonidal disease (Kundes et al, 2016) and that antibiotics should be reserved for patients with clinical evidence of infection, immunosuppression, at high risk for endocarditis or of meticillin-resistant Staphylococcus aureus infection or appear clinically septic with no other identifiable source of infection (Kuckelman, 2018).
The authors also note that treating the skin graft with a negative pressure wound therapy system could have shortened healing time. However, this is not part of the department's practice. Similarly, the use of a tie-over technique with povidone iodine has no known recommendation or contraindication and has been used by the authors' unit for this type of skin graft.
This case study demonstrates a satisfactory result, with an early return to everyday activities, in what was considered to be highly complex pilonidal disease with a high possibility of recurrence. The case study is in line with some studies that highlight the use of negative pressure wound therapy for wound healing by secondary intention, which requires fewer dressing changes, and has faster healing rates and probably lower overall cost (Farrell and Murphy, 2011).
These results demonstrated a straightforward, reliable resolution, without postoperative complications. However, the authors consider additional research is necessary before definitive recommendations can be made, particularly randomised trials with accurate descriptions of outcomes and blinding mechanisms.